Variable-speed fluid clutch



D. J. RAUN VARIABLE-SPEED FLUID CLUTCH Jan. 31, 1961 5 Sheets-Sheet 1 Filed June 13, 1958 INVENTOR. Dav/U J. Faun 63L AQM, Aff'y Jan. 31, 1961 D. J. RAUN VARIABLE-SPEED FLUID CLUTCH 5 Sheets-Sheet 2 Filed Juna 15, 1958 INVENTOR. Dov/'0 J R000 2 Jan. 31, 1961 D. J. RAUN 2,969,860

VARIABLE-SPEED FLUID CLUTCH Filed June 13, 1958 5 Sheets-Sheet 3 INVENT OR Dov/'0 J. R000 CE. LXQMN A y D. J. RAUN VARIABLE-SPEED FLUID CLUTCH Jan. 31, 1961 5 Sheets-Sheet 4 Filed June 13, 1958 -HTITV/ A INVENTOR. Dav/'0 J R000 (EX. M Af/y Jan. 31, 1961 D. J. RAUN VARIABLE-SPEED FLUID CLUTCH 5 Sheets-Sheet 5 Filed June 13, 1958 R. 0 O U T 0 W u 3 3m J Q 8m m M SP6 5. 85m 5% M N HIWWII I T H Q I l mW Hmw m 0 O H h m l mw l l B mm United States. Patent O V RIABLESPEEDYFLUID CLUTCHL David J; Raun, Palm Springs, Calif. (B.'0. Box 314, NorthriflgepCaiif.)

Filedjune, 13,1958, Sgr, N01 741,266" 6Claims.- (61:192-12);

This invention relates-to improvements: in a clntclmunit;

The principalobject of,this invention-isvto provideea clutchthat has a fullirangeofispeed variations fromrzcomplete stop to full speed ahead.

A further: objectis. .to provide .a;aclutchiithatz cannbe connected directly-to.thelarmature shaftiorrpower shaft of any. motor in place .of thelzus'ual pulley. poweriitake-ofi and-having its pulley occupying thesame relativeaposition as the original power. pulle'yt.

A further object-is'to provid'eia stationaryxcontrolufor varying the speed changes without having to; shut;:down the motivez-power in order-to makethexchangeza A still further object is to provide a-.zclu.tch.t ofiithe, hydraulic type in :which =there=are .no. excessive-.1 oil; pressuresto cause leakage.

A still further object is to. produceaarclutch which; is easy toinstall-iand onewhichzistsimpleeto manufacture.

Other objects and advantages will be apparentduring the course. of.-. the. following *description'.

In the accompanying. t drawings; forming; a :partiofi this specification and in which like numbersareiemployed. to designate like parts throughout theesamezt- Fig. 1 is a diag'rammatic View;tshowinggmyxunit ate tached'to' awmotori and employing a smultiple belt :power takeofii z Fig; 2 is a cross-.sectionalview :ofi my unitand pulley therefor, taken on.the; line:2+2I:o;'Fig.-1. and;on an enlargedascale;

Fi'gi 3 is a cross-sectional view:takenwon the line 3 3 of Fig. 2, and looking in the direction of the arrow; a portion of-thepump-plate being cutiaway;

Fig. 4 is a cross-sectional:view takenon :the .line: 4'4 of-Figr 2,. and looking in .the direction of the arrow, with a portion ofthe pump plate. removed;

Fig-=5 isa cross-sectional'view' taken onz th'e line 55 ofFig'. 2, and looking in the .directionof the-arrow;-

Figs, 6 isIa' cross-sectional view taken on. the line 6 -6 of Fi-g. 2 andal'o'oking in the. direction ofthe-arrow;

Fig. 7 is a side'elevation partly in. cross-section of the main. metering valve;

Fig..8'isi'a cross sectional viewron:the. line. 88 and looking in the direction :of the arrow. of Figt 2, showing the-brake control;

Fig. 9--isa cross-sectional view' of the meter taken-on the line 99 of Fig. 6;

Fig; 10'is a cross-sectional view taken on the line 10+10 of Fig. 6; and

Figs; 11, 12 and 13' are enlargedcross=sectional views showing the various positions of the meter valve and meter with reciprocating pistons therein:

There are many forms ofclutches, such as electrical, hydraulic and mechanical, which are used for the purpose of varying speeds between the prime mover and the driven unit. These devices are usually rather inefiicient for, the reason that in the electrical type there is a great heat loss. In the straight hydraulic type there is a tendency for the oil to heat due to its compression and 2,969,860 Patented zlam .31, .1961? .2; moving throughrestricted orifices. With the mechanical type there is undue fr'ict ion.

Applicant has therefore devised a hydraulic clutchwhiclr' is an improvementupon his former- Patent No. 2,607,242, and While employing the same metering. arrangement, the control and utilization of this metering arrangement has: been greatly improved.

In the accompanying drawings, wherein for. the purpose ofillustration :is shown :a' :preferred embodiment of myinvention; the L numeral: 5 designates a prime mover suchas an-electric motor; It is ofcourseunderstood: that any source of power may be-employed for driving the shaft 6, to'which my device-is: attached;

In order to accomplish thisi attachment, I provide -.a. shaft =7, whic'hslip'spover the 'end1of -the shaft: 6: and 'is keyed thereto *as b'y a key 8'! i This shaft-.is secured at its opposite ends to a pump housing 9, and: to which E it; is keyed as shown'at ll; i l

This housing is recessedso as *toysurround a plurality of pump gears 12, preferably: four in' number. This housing 9 i salso recessed to form chambers on eachside' of-thegears; asqsh'own at *13; Fig.:3F

Surrounding the shaft 7 "is 1 anauxiliary-shaft: 14,- i to whichis' keyedeas anlfi a drive gear: 11$

A pu'mpplate 18 is recessedi in ipumpshousing. 91' and secured therein through the medium of screws 19 which serve to posit ion and-'provide eshaftsr forthe gears .12. This pump 3 plate has a plurality *ofzpairs of ports"21,i-eaclr pair overlying. :a recessed chamber 13';3see:Figst :3 land: 4.

Communicating -with -andi"forming ac-par-t? of: each of;

' these chambers 13 "is a= channel -22 (see Fig.i3); which channel perm-its oil to: flow; toward? oria'away from-.- the pumps, formed by th'e gears -12 andilfT, dependingaupom the direction: of rotation ofithe-drive:geanlihi In ordei to relieven-purnp =pnessure:whentitrisndesired to-idle', -I pr ovide '-in the. pu'mp1 plate' lagadjacent each :of the gears, a plurality ofs'pairs. of opposed slidingwalves- 23 and 24 (see Fig. 4). These valves are normallyz h'elcl' apart-by: a I spring :26; and are adapted to release .thelarelief ports '2T in plat'e 'l8 from either. direction, dependinguponthedirection: ct -rotation of: shaft 6,: to. causethe' pump to -workflirreither-- direction.- The-nvalves 23;; 2 have aportion 23 24 respectively; which: arecsubj'ect to outlet oil pressure, depending upon the rotationi of shaft 6, seeFi'gL 4. It will beuobservedithat the meter housing 31%see*' Fig."-5, comprises a pluralityvofzcircumferentiall y spaced" recesses.- 31" which:communicatevwitlr the openings 3 3 opening into th'e bores. 35;iseecFig1: 10. When nO power= isutilized by thei pulley1'47.':oil spressune trapped in chambers-'13 inust be: relieved. tint-order itoizrstop the unit A onrever-se the motor S'.

Th'e pairsof-'-'ports 21 I communicating with:- a z'chamben 1'3 wil-l "either act as arr-outlet or retu'rnport: depending upon-.the direction of rotation 0f 'thewshaft 6zfi Thus. during idling, oil pressure generated in the chambers .13 is dir ected from one outlefpo rt -21 of 'a :pair; into'rthe bores 35; 0utof' th'e topenings"33, through-'zthez:recesses 31' and back into the other returnflport 21 of the'spair whichcommunicatewith a given chamber 13;. Itlwillibe seen that 1 during idling fluid istinternally circulated: in. the mannerdescribed: 'fioweverg in :order to. preventioi-l pressure from between the teeth of thepumpgears:12 and the -m-aim-gear 17 in' the ch'aniberssB-g "the=-re1ief: ports 27- will :be maintained open during: idling, since the; spring 26* urges the -valves- 23, 24" 'apart and: the major. portion of thepressu-re developed is circulated through: the: pairs: of portsll in the manner just described.

Positioned on. the" shaft 14" is a stationary. valve-casing. 28, which is keyed to a-slidingl valve; 29,] the operation of which will be later described.

Surrounding the-"last: mentioned valve "casingi 28 and valve 29 is a meter-*housing'fl"in-whichis"mounted""a;

plurality or free-floating reciprocable pistons 32 (see Figs. 11, 12 and 13). This housing also has bores 35 com municable with chambers 13 in which are mounted auxiliary control valves 33, which are each in turn connected to a spider 34 rotatably mounted with housing 31 on the sliding valve 29 and having axial movement therewith.

The sliding valve 29 has a rack 36 secured thereto, which rack is engaged by a pinion 37, carried by a speed control shaft 38, which may be rotated by a hand-wheel 39, the purpose of which will be later seen.

This shaft 38 is enclosed in a pipe 41, which serves to conduct oil from a supply tank 42 to the interior of the housing 43, which is attachedto pump housing 9 and rotates therein and encloses the entire structure. A hearing and oil seal is shown at 45.

The end 36' of the rack 36 is V shaped when observed in plan as indicated by shading in Figs. 2 and 7, and which end serves to spread brake pins 44 when moved to the right in Fig. 2, the ends of which pins serving to expand a spring contractible brake lining 46 against the inner surface of a pulley 47 mounted on tubular shaft 14. The pins 44 support the arake band, see Fig. 8.

The terminal end 36' of the rack 36 will only engage the pins 44 when the pulley 47 is braked and when the terminal end 36 of the rack 36 disengages the pins 44, the brake lining 46 will contract to permit the pulley 47 to rotate with the shaft 14. This disengagement occurs due to movement of the rack 36 to the left-most position shown in Fig. 2.

. It is to be here noted that the only parts that do not rotate are the speed control shaft 38 and its attached parts, the sliding valve 29 and the stationary valve casing 28 (in relation to rotation of shaft 6).

The stationary valve casing 28 serves the purpose of delivering oil from the pump gears through the ports 21 to the bores 35 and to the various chambers in which the free-floating pistons 32 travel, first passing the oil to the stationary valve casing 28, from which point the sliding valve 29 serves to receive and control the amount of oil which is fed to the opposite ends of the free-floating pistons 32.

In Figs. 11, 12 and 13. I have shown various positions of the sliding valve 29 with relation to the stationary valve-casing 28 so as to indicate the means for controlling the amount of movement of the free-fioating pistons which serve to meter the amount of oil passing through the device.

The operation of my device is as follows:

I The power unit 5 is started so that the shaft 6 is rotating and it is desired to transmit this power from my clutch to the driven unit A through the medium of the belts B, I first turn the handle 39, the initial movement of which is to withdraw the tapered nose 36 of the rack 36 from its position between the pins 44, moving the parts toward the full power output position shown in Fig. 2, which releases the spring-contractible brake band from its engagement with the inner surface of the pulley 47.

At the same time the sliding valve 29 is moved toward the left of the drawing (see Fig. 2), which tends to move the parts from the position shown in Fig. 11, and in so doing the rotating shaft 6 and shaft 7 will cause the gears to pump oil through one of the ports 21 on one side of each of the pump gears, depending upon the direction of rotation of the driving unit.

his to be here noted that by viewing Fig. 4, stop 18' will permit meter housing 31 to rotate to a limited degree with respect to pump plate 18, thus aligning certain of the ports 21 with the bores 35, also depending upon the direction of rotation. The stop 18 will project into the recesses 31 of the metering housing 31, see Fig. 5, and abuttingly engage the portions thereof in which the bores 35 are formed.

The oil issuing from the pump will pass through the ports 21 and into the bores 35 in the meter housing in which the auxiliary control valves 33 are positioned and thence through the ports 48 (see Fig. 10), thence into an annular groove 49 in the stationary valve casing, which groove widens out on one side (see Fig. 12), and allows the oil to flow, as shown by the arrow, through passages 50, into one end of the bores 35 in which the free-floating pistons 32 are located, thus forcing the pistons toward the right of the drawing, and at the same time causing oil trapped in the bores 35 to pass outwardly through the ports 51, into the chamber 52, which is open to the housing through drill holes 53 in the sliding valve 29, see Fig. 5. At the same time oil is entering each successive bore 35 and being discharged in the manner just described, oil is also entering the opposite end of the bores through the ports 51 on the reverse movement of the pistons, oil in this instance being received from ports 55 when they are rotated into alignment with ports 51, so that there is a continuous pumping of a controlled amount of oil through the meter housing. Control is effected by the sliding valve cutting off one or more of the ports 51 as the meter housing revolves thereabout. By referring to Figs. 9 and 10, it will be noted that the ports 51 are slightly out of alignment with each other a few thousandths of an inch so that this pumping operation may be very finely controlled as to the amount of oil measured by the reciprocation of each floating piston.

It is thus apparent that the travel of the controlled movement of the free-floating pistons governs the amount of oil passing through the pump and consequently the speed variation.

It is of course understood that during the metering operation each bore is taking in oil at one end and releasing it at the other, and that the amount of movement of the piston is the controlling factor in the ratio of feed control.

In order to deliver oil to the left-hand end of each of the bores, oil passes through a channel 54 formed in the auxiliary shaft 14.

It will thus be seen that I have produced a clutch which accomplishes all of the objects above set forth. It is to be understood that the form of my invention that is herewith shown and described is to be taken as a preferred example of the same and that various changes relative to the material, size, shape and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

Having thus described my invention, I claim:

1. In a variable-speed fluid clutch, a driven shaft, a pump housing secured to said driven shaft and rotatable therewith, a tubular shaft circumposed about said driven shaft and freely rotatable thereon, a drive gear secured to said tubular shaft within said pump housing, a plurality of pump gears journaled in said housing and meshed with said drive gear, a pump plate in said housing and enclosing said gears, said housing and pump plate forming pump chambers about said pump gears,- said pump plate including port means communicating with said pump chambers for permitting fluid to be circulated therethrough, a valve casing circumposed about said tubular shaft, a meter housing circumposed about said valve casing and including bore portions communi-- cable with said port means of said pump plate for receiving oil from said pump chambers, said meter housing bore portions communicating with said port means for returning fluid to said pump chambers, and sliding control valve means including valve portions in said bore portions for controlling fluid flow through said pump chambers.

2. The structure of claim 1; and relief valve means interposed between said pump chambers and said meter housing bore portions and including displaceable valve elements subject to pressure developed in said pump chambers for permitting relative rotation of said driven 5 shaft and pump housing with respect to said tubular shaft.

3. The structure of claim 2; said port means comprising pairs of ports communicating with each pump chamber, said meter housing being rotatable relative to said pump plate about said valve casing for selectively orienting the meter housing bore portions with one of said pairs of ports to permit reversing of said driven shaft.

4. The structure of claim 1; said pump plate including a relief port selectively covered by one of said valve elements, and means biasing said valve elements apart to maintain the relief port open during idling of said tubular shaft.

5. The structure of claim 1; said control valve means valve portions comprising a plurality of axially displaceable valves, a valve sleeve circumposed about said tubular shaft and axially displaceable relative to said casing and said meter housing, and a support spider journaled References Cited in the file of this patent UNITED STATES PATENTS 2,066,450 Bascle et a1. Jan. 5, 1937 2,607,242 Raun Aug. 19, 1952 2,644,561 Dikeman July 7, 1953 2,709,508 Dikeman May 31, 1955 2,839,889

McGill June 24, 1958 

